(NECN) - Tropical Storm Isaac is set to push the already rising gas prices even higher.
Oil companies have evacuated their rigs in the gulf ahead of the storm.
It's estimated that 75-to-90 percent of production could be shut down.
And that will translate to higher prices at the pumps. Right now, the U.S. average price is $3.76 a gallon, according to the Lundberg Survey.
That's up seven cents over the past two weeks.